#
# Please see this video for details:
# https://www.youtube.com/watch?v=yl8vPW5hydQ
#
code = bytearray([
  0xa9, 0xff,         # lda #$ff  # set output register B
  0x8d, 0x02, 0x60,   # sta $6002

  0xa9, 0x00,         # lda #$00  # Start at 0

  0x8d, 0x00, 0x60,   # sta $6000 # Latch out
  0x69, 0x01,         # add #$1

  0x4c, 0x07, 0x80,   # jmp $8005 # go back to first output
  ])

rom = code + bytearray([0xea] * (32768 - len(code)))


# Reset Vector
rom[0x7ffc] = 0x00
rom[0x7ffd] = 0x80

with open("rom-counter.bin", "wb") as out_file:
  out_file.write(rom)